Large-scale modeling of two-dimensional materials based moiré superlattices
数学公众报告
报告题目(Title)：Large-scale modeling of two-dimensional materials based moiré superlattices
报告人(Speaker)：Zhen Zhan (IMDEA Nanoscience)
地点(Place)：后主楼1220
时间(Time)：9月14日（周四）上午10:00-11:00
邀请人(Inviter)：熊云丰
报告摘要
Since the discovery of the superconducting and correlated insulating states in twisted bilayer graphene, a wide range of interesting phenomena have been discovered in experiments. Integrating different van der Waals materials into heterostructures and tuning their new degrees of freedom, for instance, the relative orientation and the interlayer spacing, provides a new path for engineering and manipulating nearly their electronic properties. However, theoretical studies of vdW heterostructures becomes more difficult. The main reasons are: 1) A vdW heterostructure unit cell usually contains more than tens of thousands of atoms, which is beyond the ability of the first-principles calculations; 2) The Coulomb interaction is expected to significantly modify the electronic properties and thus needs to be considered self-consistently in the theoretical calculations. Recently, a new self-consistent method by combining tight-binding model with a tight-binding propagation method is developed. An advantage of this new method is that the computational cost is linearly dependent on the size of the system. Therefore, we can extend the self-consistent calculations to systems containing millions of atoms. As examples, we investigate the novel properties and explain the microscopic mechanics of correlated properties of vdW heterostructures discovered in experiments.
[1] Yunhai Li, Zhen Zhan, et al., TBPLaS: a tight-binding package for large-scale simulation, Comput. Phys. Commun. 285, 108632 (2023).
[2] Qianying Hu, Zhen Zhan, et al., Observation of Rydberg moire excitons, Science 380, 1367-1372 (2023).
[3] Yi-Wen Liu, Zhen Zhan, et al., Realizing one-dimensional electronic states in graphene via coupled zeroth pseudo-Landua Levels, Phy. Rev. Lett. 129(5), 056803 (2022).
[4] Zhen Zhan, et al., Tunability of multiple ultraflat bands and effect of spin-orbit coupling in twisted bilayer transition metal dichalcogenides, Phys. Rev. B 102(24), 241106(R) (2020).
主讲人简介
詹真，现为西班牙IMDEA Nanoscience研究所玛丽居里学者博士后。2017年博士毕业于巴塞罗那自治大学。2017年至2022年在武汉大学物理科学与技术学院从事博士后研究。研究方向为凝聚态物理，近年来致力于低维体系中量子物态的理论研究包括采用课题组自主研发的TBPLaS 软件对莫尔超晶格电学、光学、输运和等离激元物性的研究。共发表学术论文30余篇，其中第一或通讯作者文章21篇：包括Science 1篇、Phys. Rev. Lett. 1篇、Nature Commun. 1篇、 Phys. Rev. B 11篇、npj. Comput, Mater. 2篇等。
